How Antimicrobial Coatings Lower Healthcare Associated Infections

Healthcare associated infections (HAIs) are a big problem in modern medicine. They lead to more illness, longer hospital stays, and higher healthcare costs. One of the main causes of HAIs is the contamination of medical devices and surgical instruments. Antimicrobial coatings are a promising way to reduce HAIs. They work by stopping microbes from sticking to and growing on medical devices. This article looks at the importance of antimicrobial coatings in healthcare settings. It focuses on how antimicrobial coatings lower healthcare associated infections. We also discuss how these coatings work and their uses, especially in surgical instruments and medical devices.

If you are a biomedical engineer or otherwise involved in medical device technology, this is definitely an article you will want to read until the end. 

The Burden of Healthcare Associated Infections ^1,2

Healthcare-associated infections mostly occur in hospitals; usually developing 48 hours to 30 days after treatment. These infections are a worldwide health issue. They greatly add to illness, death, and costs for healthcare systems.

These infections are especially common in intensive care units. Patients in these situations are 5-10 times more at risk to be affected by a HAI. This higher risk is due to intrinsic factors like patient immunodeficiency. However, extrinsic factors, such as from the use of medical devices, also are a big contributor. 

The World Health Organization (WHO) has established surveillance and prevention guidelines to mitigate HAIs. Despite these efforts, they are still prevalent. For example, approximately 3.2 million patients in EU countries are affected by HAIs annually, leading to 37,000 deaths. In 2015, there were 687,000 HAI cases estimated in the United States. And about 72,000 hospital patients with HAIs died during their hospitalizations. 

Common Causes of Healthcare Associated Infections

Recently there has been an increase in the number of patients suffering from catheter-associated urinary tract infections in healthcare settings. But catheters are by no means the only cause. Some of the most common causes of HAIs are related to invasive medical procedures. These include:

• Central venous catheters
• Urinary catheters
• Vascular access devices
• Endotracheal tubes
• Tracheostomies
• Enteral feeding tubes

Surgical site infections (SSIs) can also occur post-surgery. These are due to contaminated equipment or the implantation of permanent devices like cardiovascular and orthopedic implants.

The Role of Antimicrobial Coatings in Preventing Healthcare Infections

One key tool in the fight against HAIs are antimicrobial coatings. These coatings lower healthcare associated infections. These are specialized surface modification coatings. They work to stop microbes from sticking to and growing on medical devices. Specifically, they help stop the growth of various types of microorganisms, including bacteria, viruses, and fungi. 

In addition to improved hygiene these coatings also increase durability, and provide greater additional functionality.

Below we explore these helpful coatings in more detail, including how they work and their common uses. 

How Antimicrobial Coatings Work ^3-5

The term “antimicrobial coatings” is a generic one. There are different types. Each type functions through a different mechanism. Some of the most common ways these coatings work include:

1. Contact-Killing Surfaces – These coatings have antimicrobial agents like silver nanoparticles, copper ions, or quaternary ammonium compounds (QACs). They disrupt microbial cell membranes when they contact them. A contact-killing coating works by trapping an antimicrobial agent in a polymer matrix. This can be done through chemical bonding. Or it can be done by directly coating antimicrobial polymers like chitosan (CS), quaternary ammonium compounds, or antimicrobial peptides on the implant surface. When bacteria touches the surface, the coating “kills” them.
2. Release-Based Coatings – These coatings slowly release antimicrobial agents. This helps keep microbial colonization in check over time. Examples include antibiotic-releasing coatings and nitric oxide-releasing materials. Release-killing coatings are those where the surface coating acts as a drug-delivery system. The coating can release antimicrobial agents and kill the bacteria at the infection site. 
3. Anti-Adhesive Coatings – These coatings stop bacteria from sticking to the surface. They change surface features like hydrophobicity and charge distribution. This makes it hard for microbes to cling and grow on the medical device surface.

Role in Limiting HAIs in Surgical Instruments ^4-6

Surgical instruments often face exposure to harmful germs. This, of course, can increase the rate of infections. Even with strict sterilization methods, there is still a risk of contamination during use and handling. Antimicrobial coatings on surgical instruments are helpful in this area. They offer an added layer of protection by reducing microbial colonization between uses. As a result, antimicrobial coatings lower healthcare associated infections when used on these instruments.

Some common coating chemistries for this purpose include: 

• Biocompatible Polymer: This innovative approach involves the use of biocompatible materials for antimicrobial coatings. Studies show that chitosan-coated sutures work better than triclosan-coated ones. They stop bacteria from sticking and forming biofilms. Chitosan is a natural polysaccharide. It has strong antimicrobial properties, and helps improve wound healing. As a result, it is a great choice for surgical uses.
• Silver-Based Coatings: Silver ions have strong antimicrobial properties. They are often used to coat surgical instruments. This helps prevent biofilm formation and cross-contamination.
• Hydrophobic and Superhydrophobic Coatings: These coatings repel water and biological fluids, reducing microbial adhesion and simplifying sterilization processes. 
• Titanium Dioxide (TiO2) Coatings: TiO2 nanoparticles create reactive oxygen species (ROS) when exposed to UV light. This process kills microbial cells on instrument surfaces.

Role in Limiting HAIs in Medical Implants ^3,7

Implant-associated infections (IAIs) are prevalent. They are also among the most challenging complications in orthopedic, dental, and cardiovascular procedures. When bacteria sticks to a medical implant it creates a biofilm. They become very resistant to antibiotics and the immune system. Antimicrobial coatings on implants serve as a way to help prevent these infections. As a result, antimicrobial coatings lower healthcare associated infections when used on implants.

Below are some ways that antimicrobial coatings are used to prevent infections in implants. 

• Orthopedic Implants: Silver nanoparticle coatings and antibiotic-loaded coatings are often used to stop post-surgical infections on titanium and stainless-steel orthopedic implants.
• Dental Implants: Antimicrobial coatings for dental implants include chlorhexidine, silver, and fluoride. These coatings help reduce peri-implantitis, a condition caused by bacterial colonization around dental implants.
• Urinary Catheters: Release and contact-killing coatings are showing promise for lowering HAIs in this area. Results indicate they can inactivate many microorganisms for several days. Anti-adhesive coatings follow in terms of efficacy. They inhibit microbial attachment and biocompatibility.

Hydromer® Advanced Antimicrobial Coating Solutions

Hydromer®, Inc. is a medical device coatings manufacturer. Our company develops advanced, custom medical coating products, including antimicrobial coatings. These are designed to inhibit the growth of bacteria, viruses, and fungi across various applications. But our innovative solutions are particularly beneficial in healthcare settings, where preventing infections and ensuring device longevity are paramount. 

Key Features of Hydromer’s Antimicrobial Coatings:

Below are some of the key features that set Hydromer antimicrobial coating products apart: 

1. Permanent, Non-Leaching Protection: We offer surface-bonded, non-leaching, antimicrobial coatings. This class of coating forms covalent bonds with the substrate. This functionality ensures that the active antimicrobial agents remain fixed. As a result, it provides long-lasting protection without releasing substances into the environment. 
2. Durability and Efficacy: These coatings are engineered to withstand prolonged exposure to various conditions without losing effectiveness. They maintain their antimicrobial properties over time, reducing the need for frequent reapplications. They also work to improve the durability of the medical device they are applied to. 
3. Versatility Across Applications: Hydromer’s antimicrobial coatings are suitable for a wide range of substrates. This means they can be applied to many medical devices, like catheters, stents, surgical instruments, and more. 
4. Environmental Considerations: They prevent the leaching of antimicrobial agents because they are permanent, and non-leaching. As a result, Hydromer’s coatings help address environmental concerns associated with traditional antimicrobial treatments. This approach minimizes the potential development of antimicrobial resistance and reduces ecological impact. 
5. Custom formulations to meet your specific needs: All of our medical coatings can be customized to meet the specific requirements of your medical device product.

Hydromer’s antimicrobial coatings offer a robust and sustainable solution for inhibiting microbial growth across various medical applications. 

In addition, we offer a long list of services to help you reach your product development goals. These include contract R&D, contract coating, Analytical testing, technology transfer services, and more.

Contact our team today to discuss your coatings project. 

Conclusion

Antimicrobial coatings are key to lowering the risk of HAIs. They are especially important for surgical instruments and implants. These coatings help prevent germs from sticking and forming biofilms. This boosts infection control, improves patient outcomes, and lowers healthcare costs. Research in nanotechnology, biomaterials, and smart drug delivery systems will boost the field. This will result in better and safer antimicrobial coatings for healthcare settings. To tackle current challenges and meet regulations, we must effectively translate these coatings from the lab to clinical use.

References

1. Dadi NCT, Radochová B, Vargová J, Bujdáková H. Impact of Healthcare-Associated Infections Connected to Medical Devices-An Update. Microorganisms. Nov 11 2021;9(11)doi:10.3390/microorganisms9112332
2. Healthcare-Associated Infections. US Centre for Disease Control and Prevention. https://www.cdc.gov/healthcare-associated-infections/php/data/index.html
3. Wei H, Song X, Liu P, Liu X, Yan X, Yu L. Antimicrobial coating strategy to prevent orthopaedic device-related infections: recent advances and future perspectives. Biomaterials Advances. 2022/04/01/ 2022;135:212739. doi:https://doi.org/10.1016/j.bioadv.2022.212739
4. Sahoo J, Sarkhel S, Mukherjee N, Jaiswal A. Nanomaterial-Based Antimicrobial Coating for Biomedical Implants: New Age Solution for Biofilm-Associated Infections. ACS Omega. Dec 20 2022;7(50):45962-45980. doi:10.1021/acsomega.2c06211
5. Ul Haq I, Krukiewicz K. Antimicrobial approaches for medical implants coating to prevent implants associated infections: Insights to develop durable antimicrobial implants. Applied Surface Science Advances. 2023/12/01/ 2023;18:100532. doi:https://doi.org/10.1016/j.apsadv.2023.100532
6. Prabha S, Sowndarya J, Ram P, et al. Chitosan-Coated Surgical Sutures Prevent Adherence and Biofilms of Mixed Microbial Communities. Current microbiology. Feb 2021;78(2):502-512. doi:10.1007/s00284-020-02306-7
7. Teixeira-Santos R, Gomes LC, Mergulhão FJM. Recent advances in antimicrobial surfaces for urinary catheters. Current Opinion in Biomedical Engineering. 2022/06/01/ 2022;22:100394. doi:https://doi.org/10.1016/j.cobme.2022.100394